I was very fortunate and got my hands on a WO RedCat 71 from Teleskop Service about a week ago.
But I am having second thoughts because of the focuser which is very tight, the tightest I have ever experienced on any "lens". Though I haven't been able to measure the force needed to turn the focus ring, I would estimate it to be around half a kg. It is not a smooth movement when it moves.
Also the helical focus gear ratio is not sufficient to make it easy to get precise focus. In fact it's very hard to get it spot on, because moving the focus ring just a quarter of a mm makes a huge difference.
Apart from the tight focus ring, there are also almost one mm of focus backlash. Turning the focus also moves the ring about a mm back and forth in the scope length direction. To me this seems as rather high tolerances considering this is a premium product.
I have ordered a ZWO EAF, but the tightness and the backlash makes me wonder if an EAF will be able to get precise focus at all.
Has anyone else bought the RedCat 71 and do you also experience what I do?
But I am having second thoughts because of the focuser which is very tight, the tightest I have ever experienced on any "lens". Though I haven't been able to measure the force needed to turn the focus ring, I would estimate it to be around half a kg. It is not a smooth movement when it moves.
Also the helical focus gear ratio is not sufficient to make it easy to get precise focus. In fact it's very hard to get it spot on, because moving the focus ring just a quarter of a mm makes a huge difference.
Apart from the tight focus ring, there are also almost one mm of focus backlash. Turning the focus also moves the ring about a mm back and forth in the scope length direction. To me this seems as rather high tolerances considering this is a premium product.
I have ordered a ZWO EAF, but the tightness and the backlash makes me wonder if an EAF will be able to get precise focus at all.
Has anyone else bought the RedCat 71 and do you also experience what I do?
